5K30.30 - Transformer - Coil and Light Bulb

Code Number:
Demo Title:
Transformer - Coil and Light Bulb
Induced Currents Due to AC
Area of Study:
Electricity & Magnetism
Electromagnet Coil with Iron Core, Variac, and Coil with Light.

Video Credit: Jonathan M. Sullivan-Wood.

Connect the Variac to the induction coil and insert the iron core. Turn the Variac to about 20 to 40 and the light bulb will light up when placed over it.

  • John W. Jewett Jr., "Get the LED Out", TPT, Vol. 29, #8, Nov. 1991, p. 530.
  • C. L. Hamilton, J. H. Hamilton, D. A. Burba, and E. A. Jones, "Some Electrical Demonstration Using a Strong Permanent Magnet", TPT, Vol. 25, #4, Apr. 1987, p. 223.
  • Joe L. Ferguson, "Turn-By-Turn Transformer Demonstration", TPT, Vol. 17, #1, Jan. 1979, p. 59, also A Potpourri of Physics Teaching Ideas - Electricity and Magnetism, p. 151.
  • "B-425. Light under Water", DICK and Rae Physics Demo Notebook, 1993.
  • "B-260. Ring - Jumping and Heating", DICK and RAE Physics Demo Notebook, 1993.
  • David Kutliroff, "96, Extending the Lenz's Law Demonstration to Illustrate Inductance", 101 Classroom Demonstrations and Experiment For Teaching Physics, p. 211.
  • Robert Ehrlich, "N.1. Bringing a Coil with a Bulb near an AC-powered Coil", Turning the World Inside Out and 174 Other Simple Physics Demonstrations, p. 164.

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